These song sparrows like to keep their playlists fresh

MARY LOUISE KELLY, HOST:

Any parents out there will be familiar with the misery our kids subject us to when they have a new favorite song. They ask to hear it over and over without regard for the rest of us.

TAMARA KEITH, HOST:

Well, as it happens, male song sparrows seem to avoid tormenting their listeners in that way. They serenade potential mates with six to 12 different tunes.

(SOUNDBITE OF BIRDS SINGING)

KELLY: OK, that was three songs we just heard, each with a unique signature of trills and notes. Even more impressive than the execution, though, is the way sparrows string their songs together. Ornithologist William Searcy of the University of Miami says it would be easy for the birds to sing the first song, then the second, then the third and fourth.

WILLIAM SEARCY: But that's not what song sparrows are doing. They're not going through in a set order. They're varying the order from cycle to cycle, and that's more complicated.

KEITH: In other words, rather than sing the same playlist every time, they hit shuffle. Searcy is lead author on a new study about this published by the Royal Society.

SEARCY: Then what we're arguing is that what they do is keep in memory the whole past cycle, so they know what to sing next.

KELLY: Now, one of these cycles can last a long time, too - up to half an hour. Jon Sakata studies vocal learnings in songbirds at McGill University. He was not involved with the work but said he was impressed sparrows could remember a playlist that long.

JON SAKATA: I think that what's surprising about this is the scale. You know, 20 to 30 minutes is quite a long time to be cycling through a different song types.

KEITH: Sakata says there are parallels between sparrows memorizing a set list and humans recalling what we said half an hour ago in conversation.

SAKATA: You find yourself in conversation. You're like, I can't remember if I said this before, but blah, blah, blah, blah, blah. There needs to be some sort of process in my brain that has remembered what I just said. And if you find some parallels in nonhuman species, then that kind of makes you appreciate those nonhuman species, as well.

KELLY: As for why sparrows do this, William Searcy and his colleagues say they're not sure. But past work has shown that females prefer hearing a wider range of tunes, so maybe a new set list keeps things interesting.

KEITH: Either way, the work reinforces the idea that sparrows have small but mighty brains.

SEARCY: They're smarter than you might think.

KEITH: And considering all the other brainy birds, like crows and jays and parrots, that old insult bird-brained is starting to sound an awful lot like a compliment. Transcript provided by NPR, Copyright NPR.